1. Technical Field
The disclosure relates a medium processing device, such as a scanner or printer, that performs processing on a medium.
2. Related Art
Devices such as scanners and printers are sometimes provided with a planetary gear mechanism that switches motive force transmission states between a motor and a driven component driven by the motor. JP-A-2012-090007 describes an example of a configuration employing a planetary gear to switch drive states in an Auto Document Feeder (ADF).
For example, in configurations in which a source document is fed to a reader section of a scanner, in cases in which meshing of a planetary gear is switched accompanying drive of a source document feed roller, when a planetary gear and a counterpart gear mesh with each other, sometimes leading ends of the teeth of the two gears abut and do not transition to a meshed state quickly. In such cases, the distance by which the source document advances is shorter than that intended for the drive amount of the motor. As a result, reading starts regardless of the fact that the source document has not reached the reader section, raising concerns of an issue of being unable to obtain the desired reading results.